Water column displacement weight



A, L. AICHE WATER COLUMN BISPLACEMENT WEIGHT Hmm 28 MSG..

Filed July 23, 1952 NKY will:

fg/whack Patented Jan. 28, 1936 Uhll'l STATES PATEN'1 OFFICE WATER CLUMN Di SPLACEMENT VEIGHT Application July 23, 1932, smal No. 624,314

2 Claims.

The invention relates to water columns for boilers or the like with particular reference to water columns having metal weight or water displacement equipment together operating as a float to secure automatic operation that may be continuous, as to show a gauge reading at a point lower than the water level of the boiler, or that may be operative in the event of an undesirably abnormal water level, either high or low.

While intended for any use to which it is adapted, the invention is believed to have a wide and perhaps its widest and best application in water column structure and the like, of the types disclosed in United States Patent, No. 1,833,630, granted Nov. 24, 1931, upon application of David Robert Yarnall, for Mercoil alarm and indicator and United States Patent No. 1,933,132 upon application of David Robert Yarnall, for Indicator for water level and the invention has therefore been illustrated by iigures selected from these cases, modified to illustrate the new invention.

The metal weight or displacement mechanism of the character indicated normally includes oppositely acting members, one high and one low, the mechanism being moved by weight action at one of the members, then partially submerged in water (or other liquid medium herein conventionally called water) and extending upward above the line of submergence into steam (or other vapor or gas herein conventionally called steam).

The weight of the partially submerged member less its buoyant force (the weight of liquid displaced by the submerged portion of the member) is counterbalanced by an upward pull from the other member which at this time may be wholly submerged or wholly above the level of the liquid eiectively floating the first member.

A usual characteristic of metal weights or displacement members of the character indicated and operative when partially submerged by change in the elevation of the water level is a safety requirement that they be solid rather than hollow and that they present a noncorrodible surface to the hot steam and hot Water.

The latter requirement has resulted in the water displacement members (effectively weights) being usually made of cast iron rather than the lighter aluminum for example, which reacts with the hot water and hot steam under conditions frequently met in service,

(Cl. 'i3-82) A purpose of the invention is to lighten a solid metal displacement member or weight.

A further purpose is to obtain increased power through the weights by adopting a lighterV metal fill such as aluminum in an iron shell, thereby making the weights deeper than would be the depth of solid iron weights.

A further purpose is to form a weight of the character indicated by surrounding a relatively specically light interior comprising a metal 10 deleteriously reactive to hot water or steam with an exterior shell of material nonreactive to hot water or steam.

A further purpose is to fill a metal shell of cast iron or the like with aluminum or other relal5 tively light material. Y

A further purpose is to shield an aluminum weight from contact with steam or hot water by surrounding it with a shell ncnreactive to steam or hot water.

Further purposes will appear in the specication and in the claims.

I have elected to show two only of the different forms of my invention, selecting forms how- 25 ever that are practical and efcient in operation and which well illustrate the principles involved.

Figure 1 is a side elevation of a device that includes Weight structure embodying the present invention, the gure corresponding to Figure 1 of said Patent No. 1,833,630, except that the counter-acting high and low members, respectively weights at abnormally high and at abnormally low water levels, have been modified to embody the present invention.

Figure 2 is an elevation, partly in section, showing a water glass at the water level, and a plain auxiliary water glass below the water level and operated by a weight of the present inven- 0 tion, the view corresponding to Figure 1 of Patent No. 1,933,132, above referred to, except that the weight has been modiiied to embody the present invention. f

Like numerals refer to like parts in a/ll gures. 45

Describing in illustration and not in limitation and referring to the drawing:-

In the structure shown in Figure 1 a water column chamber l connects to a boiler, not shown, at lower and upper flange connections H 50 and l2 respectively, the lower connection H being well below and the upper connection I2 well above the level of the surface of the water in the boiler.

The normal water level is indicated at I3, mid- 55 way between the opposing upper and lower displacement weights Vle and l5 respectively.

The weights M and I5 operate against one another upon a valve member I6, the difference in the eiective downward purl of theweight inembers b-eing used by any suitable connections, not shown, to control the position of the valve.

Normally the lower Vweight is wholly submerged and the upper weight wholly above the surface of-the water and the weight members havesuch size and weight relations land such mechanical linkages to the Valve i6 that the valve is then maintained closed,VV the eective downward pull of the lower weight (normally wholly submerged) being then less than the downward pull of the upper weight (normally wholly above the water level) and the greater pull of the upper weight being then used to held the valve shut. Y

' If the water in the chamber il! becomes unduly high the @upper weight becomes wholly or partially submerged Yand there is a resultant upward force of buoyancy upon the upper weight which makes theclownward pull of theiupper weight less than that of the lower weight and the greater ypull exer'd by the lower weight then opens the valve.`

i'In the same way'if the water level becomes undulyglow the lower weight is wholly or partially out of the water and the resultant increase in the downward pull of the lower weight acts in the same Vdirection as before, making the lower weight Y again eiective to open the valve.

With normal Water levels, the upfper weight is predominate to an extent suicient to hold the valve shut and with either abnormally high or abnormally Vlow water a change in a buoyant force upon one weight or the other makes the lower weight predominate to an extent sufcient toppen the valve member.

K The operating iorce for either abnormally high or abnormally low wateris the difference between the downward pull of one weight as compared to that of the other, which is determined by the change'in-water displacement, and therefore is determined by the selectedV dimensions of the weights and is obviously'independent of the magnitude ci theindividual downward pulls.

While this is true, VI find that the sensitiveness of the mechanism, for a given difference between the downward pulls, is very greatly affected by changesin the actual magnitudes of the pulls,

fand that thesarne difference of Ypull react much more4 sensitively if the pulls themseives are relatively Ysmall than if they Vare relativeiy'large;

YThis is doubtless incident to the fact that triction of the mechanism varies directly with the magnitudes of the downward pnlls rather than with the dierence between the pulls.

In accord withthe present invention, the dis-- placement weights I4 and I5 are made of the saine size as before but are made relatively light ftheservice conditions, of the displacement weights may deleteriousiyreact with aluminum.

' As a result the displacement weights have in the pastbeen made of solid cast iron, preferably lof special v,composition to reduce to a minimum any deieterious reaction with the water and steam, and the sensitiveness to change has, asa

result, been less than I nd can readily be obaoeases tained by theuse of weights embodying the present invention.rv f

I provide a mere shellgextericr'i or i3 of cast iron and ll the interior or I9 with aluminum, preferably initially molten, suitably closing the pour hole withga nonreactive material. I thus obtain a displacement weight that is for a given displacement far lighter than the weights of the prior art but that maintains the nonreactivesurface of;the iron in contact with the water and steam cr the chamber.

As illustrated, the lower weight l5 has been cast ase. thin iron shell with a pour hole at 26. The interior of the shell has then been iilled wi n aluminum andY the opening at 2t closed by Y:threading the weight upon the lower erd ofthe supporting rod 2 l.

" The upper displacement weight has been cast as 'a hollow shell exterior i8 having a central periforation 22 to freely pass the Yrod 2l and pro- Fvided with pour holes at 23 anilla-finally closed after the Vinterior E9' has been filled with the initially molten aluminum by threaded connection with the lower ends of the rods 25 that support Y the upper kdisplacement weight.,Y

i The actual connections between the upper and lower displacement weights of the valve are not shown beyond thesupporting rods 2! and 25, being irrelevant to the present invention. They may be in general accord with mechanism disclosed in United States Patent No. 1,190,452, granted July 11, 1916, to D. W. Patterson, for

. Boiler'alarm.

The water column chamber I@ is illustrated as expansion chamber 2l which has-a throttled discharge into a pipe 28 and makes connection to a Bourdon pressure tube 29, `so that the Bourdon tube/expands and contracts responsively to the rise.r and Afall of pressure insidey the expansion chamber. f f

The Bourdon tube is'connected to control the opening `and closingV oigan electric circuit 30 that Y contains a light or other indicator.

When the pressure in the expansion chamberY rises, due to the opening of the valve lgthe Bourdon tube expands and Vby suitable mechanism closes the indicating circuit ata suitable switch, illustrated as a mercoid type'of switch.

Obviously the Bourdon pressure tube may eiect the opening and closing of the circuit in any suitable way and the mercury switch-shown is in- Ytended `for a conventional illustration of any switch adapted tofbe operatedV by the expansion and contraction ofthe Bourdon tube.

. The circuit of the indicator preferably includes Va light 3l at the boiler, desirably one or mere lights 32 at anyV desired Vdistant point as at--a Y board 33 for simultaneous displayof the operationc-f a number of different boilers,and also may Y complished by giving the steam in the expansion chamber 27 alternative paths of escape, through the pipe 28' to a whistle 35 or to a low pressure discharge pipe 36, and a suitable two-way valve 31 is shown for sending the steam discharge either to the alarm 35 (whistle) or to the low pressure discharge pipe 35, which preferably should connect into a heat exchanger, as for example into a low pressure heater 38.

Optionally the discharge from the pipe 36 may be tc atmosphere.

From the expansion chamber 21 the steam escapes through a throttle orice into the pipe 28 to the two-way valve 3l, which delivers it to the whistle 35 when an operating handle 39 of the valve is in low position or to the discharge pipe 36 when the handle is in raised position.

Any suitable type of two-way valve may be used and the actual structure of this valve has therefore not been shown.

The operating handle 39 of the two-way valve 3l is shown weighted to make the handle normally occupy a position to send the discharging steam to the whistle, the arm being vertically down and the weight being vertically below the valve stem 46 when the valve is in position to direct the steam to the whistle, and the weighted arm being horizontal, when the two-way valve is in position to direct the flow to the low pressure discharge pipe 35.

When the weighted arm 39 is down the discharge, if any, is through the whistle and when the arm is swung out to a horizontal position, the escaping steam, if any, is diverted to the low pressure pipe 36.

A suit-able latch member 4|, described in detail in the said Patent No. 1,833,630, cooperates with the electric magnet 34 to hold the weighted arm 39 up in horizontal position if it is raised into horizontal position during the closure of the electric circuit 3Q and is adapted to automatically release the weighted arm when the electric circuit is broken, which occurs whenever the water level becomes normal, causing the pressure in the expansion chamber 2T to fall to zero.

In operation, whenever the water level becomes abnormal, either abnormally high or abnormally low, the valve i6 opens.

The resultant pressure in the expansion charnber 2l simultaneously operates the alarm whistle 35 and expands the Bourdon tube 29 to close the electric circuit 3l), which is shown as including a light 3l at the boiler, a light 32 at any desired distant point on a display board 33 at which vit is desired to disclose the operation of the boiler, and the coil of the magnet 34.

The energization of the magnet 34 permits an operator to latch the valve 31 in position to direct the escaping steam away from the whistle, as into the pipe 36 to the low pressure boiler 38.

Figure 2 relates to water gauges for boilers of a type in which the water level I3 is located high above the operating iioor of the boiler room and from which water gauge or water level indication or record is to be provided so that the reading can be taken at the floor, or at some other point beneath the water level.

With increasing boiler pressures and with increasing sizes of the boiler unit it has become more and more diiiicult to keep track of the height of water in the boiler from the floor of the boiler roorn, and in Figure 2 the condition is relieved by the use of an inclined water gauge 25 at the water level of the boiler, and by a Supplementafl gauge 42 at a suitable distance beneath the water level gauge 26', the supplemental gauge 42 being operated by a displacement weight 43 that is advantageously or the type disclosed and claimed herein.

In Figure 2, a water column lil is suitably closed at the top by a bolted cap 44 and is provided with water and steam inlet connections at I l and l2 respectively.

The upper and lower parts of the column are shown connected through passages 45 and 46 with the water glass 23 shown as of the iiat glass variety. The passages to the glass are controlled by valves 41 and 48 whose elements are moved through rocking levers 49 and 50 operated by chains 5 l, 52 and 53.

The detail and even the fact of the existence of a water level gauge 26 are immaterial to the operation of the rest of the mechanism and are shown to illustrate thesetting in which the invention would commonly appear and the fact that the gauge 42 at the floor is auxiliary to a water column rather than to a water glass.

Tue water column may be a main column or an auxiliary water column.

Within the water column is shown a mechanisrn of the solid weight or displacement variety having the lower block 43 flexibly connected at 54 over pulleys at with a weight '56 so that the block 43 will respond to the height of liquid within the column.

As the weight 43 rises and falls with the change of water level, it aiords an accurate basis for auxiliary gauge use.

The water column is connected with the lower gauge 42 by a tube or pipe 51 within which deponds a flexible connection 58 which terminates in an indicating tube, rod or other gauge member 53 which is alined with an indicator 6B so that the bottom, or the top, or any marked portion on the indicator may be read against the scale 6l upon the surface of the gauge 42 adjoining the side opening 62 thereof.

The disclosure of a flat glass type of visual indicator is intended for a conventional showing for any indicator operatively responsive to the vertical position of the weight 43.

The iiexible connection 58 passes down through a guard 53 which may be an upward extension of tubing 5l'. Its effect is to insure settling of the sediment in the water within the space 64 in the lower part of the water column l0.

Various advantages acc'rue from trapping the sediment in the space 64. The space is so much larger in volume per unit height than is the space within the water glass indicator that the sediment may be allowed to settle for a much longer time before blowing oir.

The blowing off of the sediment from the space G4 through a suitable blow-off pipe 65 controlled by valve 65 can be effected without materially altering the now of water to the indicator 42 with the result that the connection 51 and the space within the indicator 42 may be maintained as a dead end, keeping the water cool in this dead end of the system and hence avoiding the difficulties of glass etching of the indicator surface which results from excessive temperatures with or without excessive pressures.

As in the form illustrated in Figure 1, the effective force upon the weight 43 and weight 56 is that due to the diierence of water displacement while the mass moved is that corresponding to the total weight of the two members.

The less the total weight that must be moved,

` the less will be the friction that must be overcome before the apparatus is responsive to change in water displacement.

I make the weight 43 comprise, as in the form of Figure l, anexterior shell of metal, nonreactive with hot water and steam under the conditions of service and an interior of a light metal such as aluminum.

By making the weight of lighter material than that of iron, there is more available force obtained since for a given diameter the lighter material weight can be made deeper than the iron Weight.

The external shell 61 is suitably'iron, of selected composition to make it nonreactive to water and steam .and the interior t8 is suitably aluminum,

conveniently poured molten throughV an opening in the thin shell.

It will be seen that in the forml of Figure 1 the water level is normally between the two opposing weights, the displacement action operating upon the lower weight in the event of abnormally 10W Water and upon the upper weight in the event of abnormally high water, the effect of either action being to open the valve I6 that eiects the sounding of an alarm or/and the giving of a visual indication of an abnormal condition.

In the form of Figure 2, the displacement variation always takes place at the lower weight 43 which is in effect a oat, prevented from sinking by the counterwei'ghting eiect of the higher weight 56. Y

The illustrated mechanism of Figure 2 thus shows the upper member operative merely as a weight, never as a oat so that the weight 56 may be solid iron, there being no object to provide the weight 56 with an aluminum interior.

It Will be evident that, by reducing the total weight of the weight, without the necessity of making it hollow, I decreaseV the total weight which the pulleys or other similar mechanism must bear, thus decreasing thefrictional loss and increasing the sensitivity of the weight, since the weight can indicate smaller variations in liquid level.

In view of my invention and disclosure variations and modifications to meet individual whim or particular needfwill doubtless become evident to others skilled in the art, to obtainV all or part of the benets of my invention without copying the structure shown, and I, therefore,l claim all such in so far as'they fall Within the reasonable spirit and scope 'of my invention.

HavingV thus described my invention, what I claim as new and desire to secure by Letters Patent iszn 1. In mechanism of the character indicated, a solid'l weight unit including an iron shell and an interior filling therein of aluminum.

2. In a construction operating as a float, -a weight having a shell or" relatively heavy metal which is resistant to corrosion and a solid lling of aluminum which is less resistant to corrosion,

whereby the specific gravity of the weight is less than that of the shell metal but the weight is solid throughout so as not to be subject to appreciable change in displacement in case liquid penetrates the shell, while the surface of the weight is relatively resistant to corrosion.

' ALFRED L. AICHER. 

